基于碳-碳双键定量分析的 HTPB 固体推进剂老化性能研究

During long-term storage of hydroxyl-terminated polybutadiene (HTPB) propellants, the content of carbon-carbon double bonds (C＝C) decreases over time, however, this decreasing trend can only be assessed qualitatively. Therefore, the quantitative analysis of C＝C content in HTPB propellant with different aging time was realized by liquid bromine titration. Furthermore, taking the measured C＝C content as the abscissa, the absorption intensity of the characteristic peak of the C＝C in the infrared spectrum and the maximum elongation of the propellant as the ordinate, the regression equations were fitted and the correlation analysis was carried out. The results indicate that the double bonds content decrease from 6.79 mmol/ g to 6.29 mmol/ g after aging at 70 °C for 112 days. The regression equation fitting correlation coefficients of the C＝C characteristic peak absorption intensity and the maximum elongation of the propellant are all greater than 0.9. The liquid bromine addition titration method to determine C＝C contents of HTPB propellants has a confidence level of 99%, providing a theoretical support for lifetime prediction of propellants.